"The Strategic Petroleum Reserve program provides the Nation with energy and economic security through its emergency stockpile of crude oil. As of December 31, 2007, the Reserve had a crude oil inventory of 696.9 million barrels (equal to 58 days of net U.S. imports) and a drawdown capability of 4.4 million barrels per day."
United States. Dept. of Energy: http://www.energy.gov/